1. Field of the Invention
The field of the invention generally relates to cameras.
2. Description of the Related Art
Because of the popularity of photography in today's society, numerous types of cameras are available, often with relatively expensive options. Recently numerous types of single-use, or disposable, cameras have become available.
In spite of the many advances in photography, however, the manner in which cameras take pictures has changed very little since the inception of photography. Light sensitive film is enclosed in a light-proof box. When a picture is taken, light is allowed to enter the box for a controlled length of time, and that light is focused through a lens onto a part of the light sensitive film, thereby "exposing" one picture. The film is then changed either by advancing the film from a storage spool or reel to a take-up spool or reel if the film is a continuous roll, or by removing the exposed film and replacing it with unexposed film if the film is "plate" type film. The process can then be repeated.
The many innovations to this process include advanced film winders, focus and aperture controls, and improvements in flash technology. The list of innovations is almost endless. All these innovations, however, rely upon making the basic photographing mechanism more complex, and in most cases more expensive. In light of the above, there is a need for a simplified camera design to reduce the cost of cameras, for greater ease of manufacture, and greater simplification of operation and ease of use.
Additionally, with the development of the single-use cameras, there has been an increase in the convenience of cameras to tourists, camera novices and other members of general public. Such single-use cameras, however, are often merely a plastic version of the same general design found in more expensive reusable cameras. The least expensive single-use cameras still commonly use twenty-two parts or more. With so many parts, the cost of manufacture of even the least expensive single-use cameras remains relatively high.
Moreover, conventional single use cameras must utilize separate standard film cassettes to make film removal and film handling in non-light safe environments possible. These separate standard cassettes themselves have many parts which both increase camera costs and also severely limit options for film movement and placement within the camera itself. Accordingly, there is a need for a camera which does not require a separate standard film cassette with its attendant limitations, but which still provides all the advantages of the separate standard film cassette.
Accordingly, there is a need for a single-use camera with a simplified shutter and film-advance system which minimizes the number of parts required and thereby reduces the cost of manufacture, and which further simplifies the operation of a basic camera.
In addition, conventional single use cameras have heretofore used some variations of a winding mechanism, wherein film is pulled into a roll after each successive photo. For example, U.S. Pat. No. 3,696,723 discloses a camera that utilizes a winding mechanism to pull film into a roll. However, the present invention concerns a fundamentally different pushing method whereby a small film pusher point is inserted in a film sprocket hole to thereby advance the film by pushing the film from one frame to the next.
Unfortunately, when film is pushed into a roll, certain actions occur between the layers of film, and also between the film and storage area. Film pushed into a storage area will first form an initial coil of film, the basis for a roll of film. After the initial coil of film is made from film being pushed into the storage area, additional film pushed into the storage area will form additional outer coils of film around the initial coil of film. Therefore, additional film being pushed into that film storage area to form additional outer coils on the initial coil must either cause that initial coil to slip against itself and become smaller to accommodate the additional film in new outer coils, or the walls of the storage area must move to make room for the additional film in new outer coils.
However, heretofore, film storage areas in cameras had immovable walls or were separate cassettes which had immovable walls. Consequently, as more film is pushed onto the roll, the roll cannot enlarge due to the immovable walls into which the film is being pushed. Accordingly, in designs incorporating immovable walls, the film must slip against itself and cause the innermost coil of the film to become smaller to accommodate the new coils being added. However, the high-friction of the flat film surfaces, after some initial small slippage, prevents the film from the additional slippage necessary for the inner coil to become smaller to accommodate the additional outer coils of film.
The high-friction coupled with the heretofore fixed walls of film storage areas thus limited the addition of new coils of film. Consequently, a sufficient quantity of film cannot be pushed into a storage area. Because of this obstacle, the only way to transport a quantity of film into any storage area was to pull, rather than push the film into a storage area. However, this process requires a large number of parts such as trigger members, winding knobs, pawls, ratchets, spools, and levers.
Accordingly, there is a need for a single use camera with a flexible or movable film storage area and cassette storage area capable of receiving film that is pushed therein.
Another reason that cameras utilizing push advancement rather than pulling film, or winding is that, heretofore, it has been necessary to contain film within an entirely separate cassette made up of immovable outer walls, end caps, spindles, light seals, and the like in order to safely remove film from a camera without exposing the film to unwanted light. However, even in designs incorporating movable walls of a film storage compartment or cassette storage compartment, there still remains the problem of providing a light-tight passage between the camera body and the cassette film storage compartment. This problem is made more acute since the cassette film storage area compartment is preferably molded or formed as an integral part of the camera body itself, which needs to be broken away from the camera body when exposure is complete for transportation to film developing facilities.
Accordingly, there is a need for a single use camera containing a cassette film storage area for exposed film which can be broken away from and removed from the camera body, and which has a light tight passage between the camera body and the cassette film storage compartment, with the passage remaining light tight even after the cassette film storage area is broken away from or removed from the camera body.